Buildings, particularly those having flat roofs, generally include parapets or comparable structures extending above the roof line on one or more sides. The parapets perform two functions. First, they enhance the aesthetic appearance of the building. Second, they prevent rain water and other fluids from flowing from the roof and onto the face of the building. Eliminating the flow of fluids onto the face of the building helps to maintain the appearance of the building by reducing discoloration of the face as well as helping to maintain the structural integrity of the components used for the building face.
Parapets extend above the roof line and usually terminate in a flat ledge extending the length of the parapet. The flat edge is exposed to the atmosphere and thus requires protection from moisture and the other elements of nature. Copings have been developed to cover, or cap, the flat ledge of the parapets. Generally, these copings are manufactured from metal or plastic and are designed to extend over the entire width of the flat ledge and redirect any fluids such as rain away and off of from the flat ledge.
One of the simplest copings is a single sheet of material extending the length of the parapet. While this type of coping provides some protection, designs which allow a varying width of the flat ledge and designs which provide an inclined surface for the fluid run off have significantly improved the performance of copings. These newer designs for copings include a plurality of anchoring elements or hold down cleats which are attached at predetermined spaced intervals along the flat ledge of the parapet by screws, bolts, nails or other means known in the art. Usually, some type of sealing device is attached to the hold down cleats and a cover or coping element is assembled to adjacent hold down cleats with additional sealing being provided between the cleat and the coping element. The hold down cleat usually includes some type of spacer which will provide for the inclining of the top surface of the coping element to direct fluid flow away from the building face and onto the roof top.
While the newer designs for copings have significantly improved the performance of copings, the interface between the hold down cleats and the coping element has proven to be an area requiring additional development. The hold down cleat can sag due to its own weight or form the weight of water and ice allowing deterioration of the sealing between the components and thus the leaking of fluid onto the parapet itself. In addition, the use of organic supports (plastic chairs, foam inserts and the like) is not compatible with long term durability of the coping system. Organic components can deteriorate over many years due to the high temperatures generated under the coping cover in hot sunny climates. In cold climates, low temperatures make organic components venerable to embrittlement and cracking. In intermediate climates, the continued cycling between high temperatures and low temperatures also has a detrimental effect on the durability of the organic compounds.
Accordingly, continued development of coping systems has been directed towards improved systems for holding the coping plate on the parapet and improving the interface between the coping cover plate and the hold down cleats especially at the joining of adjacent coping cover plates.